Green's thm says that if we have a simply connected region, R with a boundary C (smooth), and which is positively oriented, then we have M and N (that is, if they have continuous partial derivatives) where they are in an open region containing R...then,

Green's thm says that if we have a simply connected region, R with a boundary C (smooth), and which is positively oriented, then we have M and N (that is, if they have continuous partial derivatives) where they are in an open region containing R...then,